The goal of the proposed research is to investigate the development of infants' ability to grasp objects effectively by accommodating their hands to object properties prior to grasping the object. The experiments in this proposal are designed to (a) discover new (as yet unstudied) kinds of object properties that infants may manually anticipate, (b) investigate whether automatization of infants' actions or knowledge about optimal grasping strategies influences infants' production of these behaviors, and (c) determine whether there are learning or practice contexts that facilitate the development of these behaviors. These issues are addressed in 18 proposed experiments organized into four sections. The first section consists of studies that explore infants' anticipation of object properties that have yet to be studied, with the hope of determining whether there is consistency in the age at which infants display manual anticipatory behaviors across different physical properties of objects. The second section uses a dual-task paradigm to determine whether the addition of a second simultaneous task affects older infants' ability to display these anticipatory behaviors. The third section uses visual tasks to determine whether or not infants can differentiate appropriate from inappropriate ways of acting upon objects prior to the time that they produce these behaviors themselves. And finally, the fourth section examines three different learning contexts that may facilitate the development of these anticipatory grasping behaviors. The proposed research will add to our understanding of how young infants reach for objects and could also lead to clues about one of the most perplexing puzzles of infant research in the past 15 years: why young infants display such dazzling competencies when tested with visually-based experimental procedures, yet do not typically reveal these same abilities or expectations when tested with manually-based measures.